Seal holding device for pipe clamp

ABSTRACT

A pipe clamp including an annular clamp housing having an opening for inserting therein a pipe, opposing clamp members located near ends of the annular clamp housing, one or more tightening elements for fastening and tightening the clamp members towards each other in a direction transverse to an axial length of the annular clamp housing, and an annular seal placed in an inner perimeter of the annular clamp housing, wherein one portion of the annular seal is attached to the annular clamp housing with one or more mechanical fasteners and another portion of the annular seal is slidingly attached to the annular clamp housing with one or more mechanical fasteners so that the annular seal is permitted to move and expand radially about as the pipe clamp is tightened by one or more tightening elements.

FIELD OF THE INVENTION

The present invention relates to a coupling for pipes, and particularlyto a device for holding a seal to an inner perimeter of a pipe clampbefore tightening the clamp.

BACKGROUND OF THE INVENTION

Many kinds of removable band-type clamps or couplings (the terms beingused interchangeably throughout) for pipes exist in the art. It is notedthat throughout the specification and claims, the term “pipe”encompasses any kind of generally cylindrical object.

For example, one commercially available type of pipe coupling has anannular seal clamp housing. Clamp members are positioned face to faceand a tightening element is tightened to press an annular seal (annularelastomeric band) against the outside of the pipe inserted through theseal clamp housing. This type of clamp is particularly useful for piperepair applications, such as the pipe repair clamp described in U.S.Pat. No. 6,830,268 to Krausz, the disclosure of which is incorporatedherein by reference. The present invention is not limited to these pipeclamps, however.

Initially one end of the annular seal is typically secured to theannular clamp housing and the other end is left loose, unattached to theclamp housing. This is important because when the coupling is tightenedagainst the pipe, the ends of the annular seal abut against each other.The free end of the seal allows the seal to move and expand radiallyabout the pipe as the coupling is tightened, so that the seal alwayssmoothly and uniformly presses against and around the pipe. If both endsof the seal were fixed to the clamp housing, the seal would be preventedfrom expanding uniformly radially about the pipe as the coupling istightened. Rather the seal would bunch up, become folded or kinked, orotherwise deform, and would not smoothly and uniformly press against andaround the pipe.

However, the free end of the seal can cause another problem. Wheninitially placing the coupling about the pipe, the free end of the sealcan hang loosely out of the annular seal clamp housing. It can becumbersome for some installers to hold the free end of the seal in thehousing while at the same time placing the coupling around the pipe.

SUMMARY OF THE INVENTION

The present invention seeks to provide a device for holding a seal (inparticular, the free end of the seal) to an inner perimeter of a pipeclamp before tightening the clamp, as is described more in detailfurther below.

There is provided in accordance with an embodiment of the presentinvention a pipe clamp including an annular clamp housing having anopening for inserting therein a pipe, opposing clamp members locatednear ends of the annular clamp housing, one or more tightening elementsfor fastening and tightening the clamp members towards each other in adirection transverse to an axial length of the annular clamp housing,and an annular seal placed in an inner perimeter of the annular clamphousing, wherein one portion of the annular seal is attached to theannular clamp housing with one or more mechanical fasteners and anotherportion of the annular seal is slidingly attached to the annular clamphousing with one or more mechanical fasteners so that the annular sealis permitted to move and expand radially about as the pipe clamp istightened by one or more tightening elements.

In accordance with an embodiment of the present invention the annularseal is slidingly attached to the annular clamp housing with the one ormore mechanical fasteners passing through one or more elongate aperturesformed through the annular clamp housing. The elongate apertures areelongate in a radial direction. Additionally or alternatively, theelongate apertures may be elongate in an axial direction.

In accordance with an embodiment of the present invention the oneportion of the annular seal is fixedly attached to the annular clamphousing with the one or more mechanical fasteners. Alternatively, theone portion of the annular seal may be slidingly attached to the annularclamp housing with the one or more mechanical fasteners.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be understood and appreciated more fully fromthe following detailed description, taken in conjunction with thedrawings in which:

FIGS. 1A-1B are simplified pictorial illustrations of a pipe clamp,constructed and operative in accordance with a non-limiting embodimentof the present invention;

FIG. 2 is a simplified side view illustration of the pipe clamp; and

FIGS. 2A and 2B are simplified sectional illustrations of the pipeclamp, taken along lines A-A and B-B, respectively, in FIG. 2.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Reference is now made to FIGS. 1A-2B, which illustrate a pipe clamp 10,constructed and operative in accordance with a non-limiting embodimentof the present invention.

Pipe clamp 10 includes an annular clamp housing 12, typically made of aflexible metal sheet, such as but not limited to, stainless steel.Annular clamp housing 12 has an opening 14 for inserting therein a pipe(not shown). The ends of annular clamp housing 12 are provided with two(wedge-shaped) opposing clamp members 16. One or more tighteningelements 18 (e.g., one or more mechanical fasteners, such as a bolt orscrew and a tightening nut, and possibly washer) fasten and tightenclamp members 16 towards each other in a direction transverse to theaxial length of annular clamp housing 12 so as to apply aradially-inward clamping force on the pipe inserted in opening 14.

An annular seal 20, fashioned as a flexible inner sleeve, is placed inthe inner perimeter of annular clamp housing 12. Seal 20, withoutlimitation, may be made of a rubber (e.g., EPDM (ethylene propylenediene monomer), butyl, styrene butadiene or neoprene) or a thermoplasticelastomer (e.g., polyurethane or olefin) compatible with the fluid to becarried in the pipe.

In one embodiment, annular seal 20 is one layer of an elastomer.Alternatively, as shown in the illustrated embodiment of FIG. 2A,annular seal 20 includes inner and outer sealing rings 22 and 24radially spaced from one another. The outer sealing ring 24 includes afolded portion 26 folded over an annular abutment 28 so as to define aninner space 30, which can be in fluid communication with a fluid (notshown) flowing in the pipe. The fluid enters inner space 30 and appliespressure therein to increase tightening of the seal. The inner sealingring 22 may be removed from or added to the outer sealing ring 24 toaccommodate different pipe diameters. A type of this seal is describedin U.S. Pat. No. 6,293,556 to Krausz, the disclosure of which isincorporated herein by reference; however, the invention is not limitedto this type of seal.

One end or portion of seal 20 is fixedly attached to annular clamphousing 12 with one or more mechanical fasteners 32, such as a bolt orscrew and a tightening nut, which pass through a circular hole inhousing 12. In accordance with an embodiment of the present invention,another portion (e.g., the opposite end) of seal 20 is slidinglyattached to annular clamp housing 12 with one or more mechanicalfasteners 34, such as a bolt or screw and a tightening nut and washer.This may be accomplished by mechanical fasteners 34 passing through oneor more elongate apertures 36 formed through annular clamp housing 12.The apertures 36 are elongate in the radial direction. Alternatively,the mechanical fastener 34 can be fashioned with a sliding portion thatpermits the fastener along with seal 20 to slide radially.

In order to prevent the elastomeric material of seal 20 from oozing outof aperture 36 during tightening, a blocking element 39, such as a plateor other small piece of metal sheet (e.g., stainless steel), may beplaced on the inner side of housing 12 behind aperture 36, as seen inFIGS. 2A and 2B.

When pipe clamp 10 is tightened against the pipe, the ends of annularseal 20 abut against each other. Because one end of seal 20 is attachedby mechanical fasteners 34 in elongate apertures 36, seal 20 ispermitted to move and expand radially about the pipe as pipe clamp 10 istightened. This ensures that seal 20 always smoothly and uniformlypresses against and around the pipe. In addition, when initially placingpipe clamp 10 about the pipe, no portion of seal 20 will hang looselyout of clamp housing 12 because seal 20 is held by fasteners 32 and 34.This makes placement of pipe clamp 10 around the pipe easy and fast.

Alternatively, mechanical fasteners 32 may also pass through elongateapertures, oriented in any direction, as indicated by broken lines 35 inFIG. 2.

Alternatively or additionally, elongate apertures 36 may be elongate inthe axial direction, as indicated by broken lines 37 in FIG. 2. Thisallows seal 20 to expand axially, which may be important in certainapplications in which axial forces tend to make the seal expand axially.

The scope of the present invention includes both combinations andsubcombinations of the features described hereinabove as well asmodifications and variations thereof which would occur to a person ofskill in the art upon reading the foregoing description and which arenot in the prior art.

1. A pipe clamp comprising: an annular clamp housing having an openingfor inserting therein a pipe; opposing clamp members located near endsof said annular clamp housing; one or more tightening elements forfastening and tightening said clamp members towards each other in adirection transverse to an axial length of said annular clamp housing;and an annular seal placed in an inner perimeter of said annular clamphousing; wherein one portion of said annular seal is attached to saidannular clamp housing with one or more mechanical fasteners and anotherportion of said annular seal is slidingly attached to said annular clamphousing with one or more mechanical fasteners so that said annular sealis permitted to move and expand radially about as said pipe clamp istightened by one or more tightening elements.
 2. The pipe clampaccording to claim 1, wherein said annular seal is slidingly attached tosaid annular clamp housing with said one or more mechanical fastenerspassing through one or more elongate apertures formed through saidannular clamp housing.
 3. The pipe clamp according to claim 2, whereinsaid elongate apertures are elongate in a radial direction.
 4. The pipeclamp according to claim 2, wherein said elongate apertures are elongatein an axial direction.
 5. The pipe clamp according to claim 1, whereinsaid one portion of said annular seal is fixedly attached to saidannular clamp housing with said one or more mechanical fasteners.
 6. Thepipe clamp according to claim 1, wherein said one portion of saidannular seal is slidingly attached to said annular clamp housing withsaid one or more mechanical fasteners.
 7. The pipe clamp according toclaim 1, wherein said annular seal comprises one layer.
 8. The pipeclamp according to claim 1, wherein said annular seal comprises morethan one layer.